basses for newbies (SX batch build thread) Part 2

[joeyl]

nice can't wait to hear the prototypes.

[daveman50]

Originally Posted by chunger

1. Un-Sung Musical Intruments Co., Ltd.

Sorry, can't pass that up. The unsung hero? A nice play on words for a musical instrument company. (Not that they know what it means in English.)

[TheSuzie]

Originally Posted by chunger

I had a chance to closely look at a few manufacturers at NAMM, and within my price window, none of the instruments measured on par with what I have seen from the factory I've been talking to especially on the fretwork.
..........

1. Still make base "Chunger Standard" instruments available "right off the boat".
2. PLEK all and price accordingly.
3. PLEK as upgrade option on "chunger standard"

I'm going to insert two cents and mention that the wood is #1 here. Nice fretwork and/or Plek jobs don't mean much if your supplier does not supply good, properly dried wood and frets that stay where they were put. This is one danger that you face as a new customer of an offshore builder. I have had some great inexpensive imports that were very stable and also seen some necks that were not much better than a wet noodle. I have also seen build quality so shoddy that I would not waste significant money or time upgrading the instrument. You must be sure that the builder understands your minimum quality requirements and will follow through. You put a lot on the line when you put your name on the instrument.

I'm sure you know this already but I worry about going on what you see at a trade show. People bring their absolute best. I always wonder how the product that comes out of the containers stacks up against those samples.

Best of Luck,
S

[chunger]

This is why I am moving very cautiously in regards to an overseas supplier. There are tons of horror stories out there, and while you think the trade show folks will be bringing their best to the shows, for the most part, what I handled on the floor at NAMM was unacceptable for my standards.

I spoke with the few suppliers that had instruments within a workable range of quality. Working with the SX's has been enlightening. I do not believe all of the SX parts come from the same factory. I've encountered several different "types" of parts with slightly different built methods. But, what this experiment has shown is how much crap you can get away with on the build of an instrument including imperfections in wood, varying dryness, obviously messy assembly, and still come out in the end with an instrument that plays and sounds great.

Certainly, on a cost-no-object custom build, all of these variables would be under complete control from start to finish, but when trying to deliver something in the $500-$700 range, life is full of gigantic compromises.

I will, however proceed with much caution.

-'Chung

[chunger]

Adventures with bass #18. . . well, the good news is it's done. . . the bad news is, I think I've put about 6 extra hours into this bass that I have not accounted for.

First off. . . the NJ4SE's that were originally installed did not sound quite right. Output was lower than expected, and a little thin sounding. Knowing how ballsy these pickups are, I suspected something was wrong, and the easiest way to confirm was to simply put in another set and see if the condition changes. As you probably know, my recent Nordstrand order went through severe delays. This pickup was in that recent order.



Luckily, this was the first instrument I implemented my quick-change pickup connectors on, so the actual pickup swap was breezy.

But, I simply could not get this bass to play to my liking. It was buzzing a lot, and I tried all manner of truss rod settings from nearly flat to large relief, and while I did find an optimal setting, I knew it could be better. I was cursing that expensive German robot that leveled these frets

But, since I'd spent all this time and money getting this bass PLEK'd, I had some solid data I could look at to determine precisely where the problem was as opposed to hacking in with my leveling block by feel only. The following image is posted at full resolution if you want to zoom in.



the first problem that was detected with my fret rocker was fret 15. As you can see on the graph, it's quite high on the E and A strings and marginally high on D and G strings. I don't know what the robot was thinking, but I suspect because those end frets were below the programmed 12 degrees of falloff, it simply did not cut them allowing the original un-eveness to remain.

The least intrusive way to get rid of that was just go in with my crowning file and slowing, carefully, lower just fret 15 until it was even with the 2 adjacent frets. This helped my buzz situation, but I was still displeased with the bass was playing overall. I was getting consistent buzz all the way up and down the fretboard, so I knew this was not isolated to a single high fret, or if it was, the problem was still high up in the neck in the fall-away region (fret 12+)

So, looking back at my graph, I figured the next problem that was not allowing me to run super-fast action was a hump at frets, 13-15 as well as the last fret 21 being high.

From previous experience with the same symptoms, I was able to improve things by cutting a bit more fall-away, so that's what I set up to do.



And, a shot of my final cut after a few cycles of re-stringing and testing.



My main concern was setting my cut angle so I would hit frets 13 and 14 but not hitting the 2nd to last fret (20) too hard. In the end, I grazed fret 12 slightly.

At this point, the bass came together in terms of action, and I re-dressed the frets that I re-leveled. Because this bass is going to Eric, who is an established upright bass player just making the transition to electric, I raised the action to just below .100" at the E string and ~.087" at the G string. Still well below a lot of factory setups, but very smooth playing. Even though I prefer lower action, I would have no problems getting around on this setup.

Next, I installed a set of Genuine Fender knobs. . . I went with non-knurled pots on this bass because it's one of the prettier ones, and I thought it would be nice to "go crazy" and do the nice knobs on it.



Bass #18 finished. Eric has been extremely patient. We discussed building this bass Nov. 18. I let him know he was free to run it with the slightly not-perfect pickups since the bass worked just fine, but he opted to wait until I got it all sorted out.

Well, another bass done, and lots learned in the process. .. so, 'till next time. . .

[KingRazor]

Anyone here know if SX basses use 1/2 inch or 3/8 inch tuners?

[joeyl]

question: Chunger, in one of your posts, you mentioned a digital scale that you bought from Amazon but I cannot find it anymore, do you mind posting it again? thanks

[MooseLumps]

Short sample clips of #16.

[KingRazor]

Originally Posted by chunger

One thing I did discover and would tentatively recommend is a lead-free type temperature controlled soldering iron. I am not using lead free solder, but the difference between this iron and the regulated iron I was using before is stunning.



First off, this thing came up to temperature in probably under 5 seconds. I wasn't expecting it to "beep" so soon after plugging in, and I honestly thought something was messed up because the temp reading on screen couldn't possibly be actual tip temperature! But it was. Incredible. I can shut down this iron between processes because I don't have to wait for it to come back up to temperature when I need it next. It also has a lot more power 70 watts instead of 40 watts. But, I think what it's doing is sampling tip temperature much more frequently than the previous iron and throttling the power up and down actively to maintain tip temperature. The end result is I am able to solder smoothly at much lower temperature settings which is awesome. When solder things like copper foil that dissipate heat so fast, I have this new iron set a full 100 degrees C lower than my previous iron to make the same solder joints. That's worth a little extra money to me. Time will tell whether this tool holds up. I had part of the iron retainer break on the Aoyue 937+ I had earlier. I purchased a replacement part (costing nearly the same as the iron), and after studying pictures, decided the new on (Aoyue 2900) looked more robust and not prone to the same failure, so I stuck it on my Amazon wish list, and my brother in law bought it for me over the holiday. With the amount of soldering I'm doing these days, the monumental jump in performance is very welcome!

Amazon.com: Aoyue 2900 Lead Free Soldering Station: Home Improvement

try it. . . you too will be amazed

I was looking at getting the 937+ but this is less than $20 more right now. Putting it on my birthday list.

[chunger]

Originally Posted by joeyl

question: Chunger, in one of your posts, you mentioned a digital scale that you bought from Amazon but I cannot find it anymore, do you mind posting it again? thanks

I'm using a "myweigh" ultraship scale. Can't remember if I'm using the 55 lb. or the 75 lb. capacity one.

Amazon.com: My Weigh - Ultraship 75lb / 34kg Electronic Digital Shipping Postal Warehouse Scale - All Black with Blue Back Lit Display: Office Products

Please buy from a reputable company with a good return policy and customer service. It seems from recent amazon reviews that the quality can be hit or miss as with many Chinese products. The scale has been accurate enough for many common uses (postage, dog food, bass guitars, etc.) NOT accurate enough for say, ammunition reloading

Originally Posted by MooseLumps

Short sample clips of #16.

Nice Mooselumps! I wish I had a chance to record samples of #16 before it left the sweatshop. Great to hear it again. Tone for days.

[chunger]

It's been hectic lately trying to shuffle the right basses to the right people. . . Jasaman thinks #18 won't be the best fit or Eric. Uriah Duffy sat with it though for a while after one of Jasaman's gigs and really liked it for his style which has a lot more fast, aggressive upper register tapping. Being a serious tinkerer himself (he built all of the basses he plays), he recommended a heavy brass bridge, and I think he may be right. One of the reasons I think #16 ended sounding so good with the NJ4SE's was it's unusually heavy body that might have behaved similar to a high mass bridge.

For now, what we plan to do is swap out #1 (currently living in a middle school music program) to Eric and set it up with new pickups. . . then, sell #18 to the middle school. I'll put some blue strings on it. The kids will flip out and love it.

A little feedback on the student side of things. All of the junior high kids that bought these instruments have been extremely happy and have been progressing well. #12 (black on black P), #13 (white P), #10 (white P/J). Jasaman sees a lot of them regularly at lessons, and it seem there has been no desire for any of them to buy other instruments. The basses are settling in and breaking in really well. The situation at the school music program with #1 is also good. Many non-bass player kids have been able to be taught songs on that instrument and actually get through them. I think the success helps draw the younger kids towards the instrument! So, the core objective of this project is going very well indeed.

Now, back to the scheduled programming

It has been crazy with schedules lately, and I haven't had a chance to line up a studio session, so I decided to just go ahead and move forward with pickup testing. #3 has gone through enough configuration changes for several lifetimes and is finally settled down to a really lovely sound, so the focus now shifts to #9 as my pickup test mule. As a refresher, #9 currently has the "Prototype A" jazz pickup made for me by Mike at Nordstrand. It is really sounding fantastic as is. The only nitpick I have with it is its copious amounts of treble. Very sweet, harmonic treble, but a lot of it. This is an Alnico jazz pickup with p-bass coil depth wound to ~10K with thin coil wire. Straight wind. This pickup has a lot of lower midrange growl and articulates forward in the mix pretty aggressively. Awesome if you're playing the right notes. . . if not, well. . . let's just say it's a bit hard to hide with this one Bridge pickup soloed. . . ahh. . . a burpy treat.

I had a few issues with the recent batch of pickups ordered from Nordstrand. Let's talk about the 1st pickup I tested. From a previous post, I noted complete disassembly of a stock SX pickup to discover the coild depth was slightly deeper than a p-bass @.350". This pickup has a .350" coil depth. I also shortened the magnet length back to standard jazz bass length which would theoretically reduce bass and treble response, but would reduce treble much more drastically than bass. Unfortunately, there must have been a slight mis-communication, and this pickup arrived with a DC resistance of 7.12K neck, 7.43K bridge. One of the items I discussed with Carey was the possibility of using thicker, more standard coil wire on the .350" depth setup. I suspect this was wound with standard NJ4 coil wire, and the bobbin is very full. Probably at the limit full to reach this output. I did not feel this pickup as it stands would carry forward very well in testing due to the drastic difference in DC resistance. It is in a completely different range than my ~10K prototype A that I feel is very close. Nevertheless, it is a configuration I would not have ordered; I have it in hand; so I figured I'd at least throw it in and hear it.

So, #9 goes under the knife again.


The first thing I did in preparation for pickup testing is modify the wiring harness with my new quick-disconnects. . . since I bought a pile of them



and, pickups go in:


Note: another small detail that was missed is I did not specifically order the nice bead blasted, rounded pickup covers that I like so much. I will have to be more specific in my next order. Typically, I would just re-use the current covers, but the prototype A pickup was hot-glued to the cover because these short coil setups are a bit difficult to keep pressed up inside the covers.

And, all buttoned up, ready for testing:


The sound from this pickup was interesting. The coil depth is a big part of the "SX sound" that is very distinctive. . . a bit of a snarly tone, and this pickup exhibited that to a certain extent. It is also very even, articulate, and open. . . airy sounding, but to my ears and fingers didn't hit and have the weight that I like to hear in a pickup. Quite interesting actually, but it confirmed my preference for a pickup wound hotter. I will send this unit back to have the chassis re-wound with thinner wire to 10K.

The next pickup I tested is the same as the current prototype. . . well, it measures a smidge hotter at 10.76K neck, 10.98K bridge. Its coil depth is standard p-bass depth like the current prototype but the magnets have been reduced a little back to standard jazz bass depth, and instead of the straight wind, we implemented Nordstrand's CNC simulated handwind. So, the magnet was reduced some, and it must have more turns on it to match or exceed the output with the longer magnet.

the quick-change connectors really worked out well. Pickup changeover probably took all of 5 minutes.

Ok. . . the playing this pickup. This one is obviously much closer to the development path I'm seeking and yes, the main objective of taming the treble response was achieved. I can see how the simulated handwind evens out some of the peakiness of the response as well. Very close. . . except. . . on the E string I feel a bit of hollowness. Very, very similar to the feeling I had with the stock Nordstrand P-bass pickup. Some might call it "grind". Listening again to the bass acoustically, I confirmed that the frequencies that I want to hear are in there in the instrument, and I did not have this impression with the original prototype A pickups. It is very subtle, but for some reason it is in a spot in the frequency spectrum that I feel is critical for the sound I'm going after. A-G strings sounded absolutely fantastic! But, if I had to pick between too much treble up top or hollowness on the lower notes of the E string, I would choose to have it full down low and deal with the "extra" treble especially since it is not objectionable or harsh in any way. Always easier to dial back some excess than try to boost something that is missing. The pickup also sounds a bit more choked or veiled than the original prototype A probably due to it being overwound by comparision.

So, after thinking about it for a while, I think my best hope will be in the .350" coil depth solution to slightly decrease the snarl of the pickup (slightly less mid-aggressive), use the slightly longer magnets to get my bass response back, and see if the simulated hand-wind by itself will tone down or spread out the treble spike to a friendlier level. . . then, wind it out to 10K on the neck pickup and naturally, slightly higher at the bridge due to it being physically longer.

Some people will probably think I'm out of my mind and totally splitting hairs, but careful development on the front end and a bit of a monetary hit for various prototypes resulted in what I feel is an astounding custom p-bass pickup. I want to have the same qualities in a single coil jazz bass pickup and I think I'm very close.

Gotta give Carey a call. . . more to come.

[chunger]

took a step back. . . played some sand volleyball today. . . came back home in a relaxed frame of mind and played the new pickup again on #9 for a good hour. . . without pre-conceived notions. I see where Carey was going with this pickup based on my feedback from the previous iteration. . . it is creamier and much more controlled. Harmonics are sweet and articulate, and the scoop at the E string is so slight that I would venture most people. . . probably even Jasaman would not notice.

Passive pickups. . . I guess it's all about getting a good balance, and I have obtained an awful lot of the things I want already. I like that the Nords are open enough to allow the characteristics of the wood on each bass to come through unlike some of the other pups I've tried that tend to mask a lot of that. Certainly these custom nords put a sonic imprint on the instrument in a nice, in-your-face sort of punchy way that I have always liked the stock SX pups for. . . but still sing and are extremely nuanced.

A note to self about development. I should have altered only 1 variable at a time instead of changing 3:

1. Wind pattern
2. number of turns
3. magnet length

Even though the changes were all relatively slight, I can't tell which specific spec change contributed which sonic shift. I will endeavor to be more methodical and stick to my step-by-step approach.

On the bright side, I think I have a very usable pickup in this current prototype and will be able to use it on a build.

[bassbenj]

Originally Posted by chunger

With the amount of soldering I'm doing these days, the monumental jump in performance is very welcome!

Amazon.com: Aoyue 2900 Lead Free Soldering Station: Home Improvement

try it. . . you too will be amazed

I want to chime in with Chunger as to the importance and utility of a temperature controlled iron even if you are NOT doing massive amounts of soldering. The KEY to the whole thing is that temperature controller shortens a long annoying startup cycle to where you can "almost" turn the iron on and off as you use it. Plus, the controller reacts to the weight of the material you are soldering applying more heat to heavy items like copper foil and backing off on thin things like pot lugs to keep from scorching them.

The bottom line is that BEFORE you get one of these it all seems like too much money to no good purpose. AFTER you'd never live without it. Take our word for it! It's NOT too much money and WELL WORTH the price!

This seems like a VERY nice unit for the money. Cost about what I paid for my current Radio Shack Temp-controlled unit, but seems much nicer. I like the solder roll holder! Whatever excuses you are cooking up not to get one of these, let me tell you they are WRONG. Just DO IT. You won't be sorry.

[tk421]

i concur. heartily, even. i attribute my horrible inability to solder anything other than 2 wires together to my only equipment, a horrible 20 year old 130w weller / Radio Shack monstrosity. it is always WAY too hot or WAY too cold, and no in-between.

a proper, dedicated station is always the way to go. there is a decent one at work up for grabs, and i think i'm on it. lol.

@ Chung -

when in doubt, step back. if you get too close, you can't see the forest for all the trees. a lot of times, i find the quickest way to solve a problem is to not think about it too hard. something eventually pops in up there.

[chunger]

My brain has been working the pickup issue lately, so a few pics. . .



this is the original prototype that Mike made for me (no longer with Nordstrand). A few questions came up after my last round of prototyping so I figured I'd take a look inside. I didn't previously because these were hot-glued to the covers. I had to cut and scrape the hot glue out to free the pickup from the cover. . . all while being very careful not to dig too deep and possibly damage the delicate coils.



I believe these are wound with 43 gauge SPN wire with a p-bass coil depth to 10.06K and 10.44K dc resistance. No simulated hand-wind.

This is the .350" coil depth prototype that is 7.44K. . . I think it's either using the heavy formvar wire or 42 SPN because even though the coil is deeper, the pickup is very full compared to the other prototype. Notice how the coils actually bulge past the bobbin. This pair has been shipped back to Nordstrand to wind to 10K as they are not in the range I'm aiming for tonally. Hopefully, I will get more specific data back on the next round (number of winds, etc.) so I can get back on the right development path.





At any rate, I've been reading about pickup winding lately, and it's fascinating stuff. Wind patterns and wire types, and wind tension, hand-wind vs. CNC control, etc. All effect the end-response of the pickup. No wonder it's very difficult to find an inexpensive pickup that goes the distance. . . even by some of the big-name companies.

With the technical snags that delayed the last batch of prototypes, part of me is thinking: "Go ahead. . . build a DIY CNC winder and start prototyping this stuff yourself." But, I'm thinking that would be a HUGE can of worms to open right now. Best let the folks who actually know what they're doing sort out the finer details.

The information about winding still seems to be more closely guarded than DIY audio electronics and luthiery in general where folks seem to be sharing and pushing boundaries with the internet as a vehicle for the flow of ideas. People are very guarded about their processes and formulas as they relate to specific pickups. It does seem, however that a lot of home-brew winders experience success on the first few attempts as long as they are not straying too far from the known, traditional patterns.

[KingRazor]

Been slowly modding my SX Ursa and it looks like my bass is slightly out of alignment:



I'm going to try drilling the body holes a bit wider and see if I can move the neck a little to correct the alignment.

After I get all the wiring done I'm taking it in to get the new graphtech nut installed and have it set up with Circle K strings.

[swartzfeger]

This thread has really inspired me! I have a SX fretless that's basically been orphaned since I bought my new Bongo 5str fl.

I'm jonesin' for an epoxy fingerboard sound, which I won't do to my Bongo's pau ferro fingerboard, so the SX would be a good candidate.

What I'm wondering is if anyone has expoxied/CAd their SX fretless fingerboard? I expoxied a fingerboard 20+ years ago and don't really look forward to doing it again!

Also, Chunger -- I haven't read thru all 50+ pages, but I noticed in some pics you had replaced the stock bridge with a new one... which brand is it, it doesn't look like a LQ BA. Did it make a significant difference?

[chunger]

I'm using the Babicz FCH bridge. . . let me know if you need one. It is not as heavy as the BA bridge so to my ear, it does not alter the inherent sonic characteristics of the instrument as much, but it's a well engineered piece and I've found it beneficial in the couple of basses I've installed it on.

[swartzfeger]

great info, thanks! their bridge design looks pretty innovative.

[MglMatador]

Originally Posted by swartzfeger

great info, thanks! their bridge design looks pretty innovative.

The high mass bridge sold by Rondo is not too bad, especially for $20.

I bought two extra 'old headstock' fretless necks back last summer when Kurt offered them. I'm planning on epoxying at least one of them so maybe I can give some feedback this summer.